1. Field of the Invention
The present invention relates to a manufacturing method for a wafer lens module and the structure of the wafer lens module, and in particular to a method using a high temperature plastic material for manufacturing the wafer lens module and the structure thereof.
2. Description of Related Art
People are sensitive to visual images and instinctively attracts to and response to visual cues generated by the images. Generally speaking, image device is widely used in many applications for attracting people's attention. For example, lens module is used in the mobile phone system so that people can see each other when talking on the phone.
Please refer to FIG. 1, a traditional wafer lens module is shown. Therein, the wafer lens unit 1′ is, for example, a 2G (2 glass) lens unit. The wafer lens unit 1′ has a lower wafer lens module 10′ and an upper wafer lens module 11′. The lower wafer lens module 10′ includes a substrate 101′ made of glass material, a first upper optical lens 102′ disposed on the top surface of the substrate 101′, and a first bottom optical lens 103′ disposed on the bottom surface of the substrate 101′. The first upper optical lens 102′ and the first bottom optical lens 103′ have different optical properties, i.e. negative and positive lens. Similarly, the upper wafer lens module 11′ includes a substrate 111′ made of glass material, a second upper optical lens 112′ disposed on the top of the substrate 111′, and a second bottom optical lens 113′ disposed on the bottom of the substrate 111′. The above-mentioned lens module is formed by packaging the upper and lower wafer lenses on the substrates. Furthermore, a first spacer 12′ is disposed between the lower wafer lens module 10′ and the upper wafer lens module 11′ for meeting the requirement of the optical path. The first spacer 12′ also can protect the optical lenses 102′ and 113′ from scratches. Similarly, a second spacer 13′ is disposed under the bottom surface of the substrate 101′ and the first bottom optical lens 103′ of the lower wafer lens module 10′ is surrounded by the second spacer 13′ for protecting the first bottom optical lens 103′ from scratch. Traditionally, the spacer is mounted on the wafer lens unit 1′ by post processing method, for example the spacer is attached on the glass substrate by gluing. For example, the second spacer 13′ is attached on the bottom surface of the lower wafer lens module 10′ by glue method. Therefore, there is a glue layer between the spacer and the substrate. It is thus necessary to control the thickness of the glue layer because the thickness is critical for the outputting image. In other words, the optical axis of the upper wafer lens module may not align to that of the lower wafer lens module because of the un-uniform thickness of the glue layer to cause the image to deviate from an accurate focus.
Furthermore, the aforementioned spacer is made by ordinary plastic materials which are easily deformed and the dimensions of the spacer are not as precise for the reason of the manufacturing method for the spacer. Therefore, in assembling step, the mis-alignment of the upper wafer lens module. 11′ and the lower wafer lens module 10′ causes the optical axis of the upper wafer lens module may not align to that of the lower wafer lens module and the image quality is decreased.
Therefore, in view of this, the inventor proposes the present invention to overcome the above problems based on his expert experience and deliberate research.